CN-122011376-A - High-strength high-temperature-resistant antistatic PA10T composite material and preparation method thereof

Abstract

The invention discloses a high-strength high-temperature-resistant antistatic PA10T composite material and a preparation method thereof, wherein a composite chain extender IPDI-CNT-G is formed by utilizing the activity difference of two isocyanate groups of isophorone diisocyanate and covalently bridging carboxylated carbon nanotubes and aminated graphene through stepwise controllable reaction. The composite chain extender is applied to an in-situ polymerization process of PA10T, an IPDI component of the composite chain extender can participate in a terminal group reaction of polyamide to realize chain extension, and simultaneously CNT and graphene are firmly introduced and fixed in a polymer matrix in a chemical bond form to construct a high-efficiency stable three-dimensional hybridization conductive network. The prepared PA10T composite material has excellent mechanical property and heat resistance, volume resistivity reduced to 1.0X 6 ~10 9 Ω & cm, lasting and reliable antistatic function, and is especially suitable for precision electronic and electric appliance and automobile industry fields with strict requirement on electrostatic protection.

Inventors

• ZHENG YUYING
• Chen Dengya

Assignees

• 福州大学

Dates

Publication Date

20260512

Application Date

20260325

Claims (7)

1. 1. The preparation method of the high-strength high-temperature-resistant antistatic PA10T composite material is characterized by comprising the following steps: (1) 1, 10-diaminodecane, terephthalic acid, sodium hypophosphite serving as a catalyst and antioxidant 1010 are dispersed in deionized water by ultrasonic waves; (2) Transferring the dispersion liquid obtained in the step (1) into a high-temperature high-pressure reaction kettle, and stirring and reacting for 2 hours at 80 ℃ and 0.1MPa under the nitrogen atmosphere to obtain PA10T salt; (3) Heating for the second time under the condition of keeping stirring, heating to 240 ℃, and maintaining the pressure to 2.0-3.0 MPa for 4 hours; (4) Adding a composite chain extender IPDI-CNT-G into the reaction kettle, and continuously reacting for 2 hours at 240 ℃ and 2.5 MPa; (5) And (3) decompressing and cooling the reaction kettle, placing the prepolymer in a glass culture dish, placing the glass culture dish in a high-temperature vacuum drying oven, carrying out solid-phase tackifying for 4 hours, and then naturally cooling to normal temperature to obtain the high-strength high-temperature-resistant antistatic PA10T composite material.
2. 2. The preparation method of claim 1, wherein the raw materials comprise, by weight, 52 parts of 1, 10-diaminodecane, 50 parts of terephthalic acid, 2-6 parts of a composite chain extender IPDI-CNT-G, 0.1 part of sodium hypophosphite as a catalyst and 1 part of antioxidant 1010.
3. 3. The preparation method of claim 1, wherein the composite chain extender IPDI-CNT-G is a complex formed by isophorone diisocyanate IPDI molecules bridging carboxylated carbon nanotubes COOH-CNT and amino functionalized graphene NH 2 -G through covalent bonds, wherein high-reactivity isocyanate groups in the IPDI molecules form amide bonds with carboxyl groups of the COOH-CNT, and residual low-reactivity isocyanate groups in the IPDI molecules form urea bonds with amino groups of NH 2 -G.
4. 4. The preparation method according to claim 3, wherein the composite chain extender IPDI-CNT-G is synthesized by a step-by-step controllable grafting process, and comprises the following steps: 1) Performing acid oxidation treatment on the carbon nano tube to obtain carboxylated carbon nano tube COOH-CNT with the surface rich in carboxyl, and performing chemical reduction and amination treatment on graphene oxide to obtain amino-functionalized graphene NH 2 -G; 2) Dispersing COOH-CNT in anhydrous polar solvent, reacting with IPDI under 40-60 ℃ for 4-8 hours in the presence of protective gas and catalyst, controlling total dosage of IPDI to make molar ratio of-NCO group to-COOH on CNT surface be 1.5:1, reacting with IPDI high-activity-NCO to generate IPDI-g-CNT intermediate, and retaining low-activity-NCO; 3) The second bridging step, namely adding NH 2 -G dispersion liquid into the IPDI-G-CNT reaction system under the condition of not separating intermediates, and continuously reacting for 24 hours at 60 ℃ to fully react low-activity-NCO remained on the IPDI-G-CNT with-NH 2 of NH 2 -G, wherein intermittent ultrasonic assisted dispersion is adopted in the process; 4) After the reaction is finished, the mixture is poured into methanol for sedimentation, and is filtered, washed and dried for 48 hours under 80 ℃ in vacuum, so that the black powdery composite chain extender IPDI-CNT-G is obtained.
5. 5. The process according to claim 4, wherein the catalyst in step 2) is dibutyltin dilaurate, the anhydrous polar solvent is anhydrous N, N-dimethylformamide, and the shielding gas is nitrogen.
6. 6. The method according to claim 4, wherein the intermittent ultrasound-assisted dispersion in step 3) is carried out for 5min every 3 hours during the reaction, allowing the powder dispersion to react well.
7. 7. A high strength, high temperature resistant, antistatic PA10T composite material made according to the method of any one of claims 1-6.

Description

High-strength high-temperature-resistant antistatic PA10T composite material and preparation method thereof Technical Field The invention relates to the technical field of polymer composite materials, in particular to a high-performance semi-aromatic polyamide composite material. More particularly, the present invention relates to a poly (terephthaloyl) decamethylene diamine (PA 10T) composite material and a method for preparing the same, which simultaneously achieve high molecular weight and high-efficient antistatic function by introducing a composite chain extender based on isophorone diisocyanate (IPDI) bridging Carbon Nanotubes (CNTs) and graphene (G). Background Poly (p-phenylene terephthalamide) (PA 10T) is a semi-aromatic high temperature resistant polyamide with excellent properties. The monomer decanediamine is derived from renewable resource castor oil, and has green and environment-friendly characteristics. The PA10T molecular chain contains both rigid benzene ring and flexible methylene chain segment, so that the PA has the advantages of high melting point (about 316 ℃), excellent heat resistance, good dimensional stability, low water absorption, chemical solvent resistance and the like, and has wide application prospect in the fields of electronics, electricity, automobiles, aerospace and the like. To impart antistatic properties to PA10T, conventional approaches are to directly blend conductive fillers such as carbon black, carbon Nanotubes (CNTs) or graphene. However, these nanofillers are highly susceptible to agglomeration in the polymer melt due to the extremely high specific surface area and strong van der waals forces, resulting in maldispersion. This not only results in high filler addition levels required to reach the desired conductivity threshold, but also severely compromises the mechanical properties of the material, especially impact toughness. In addition, physically blended fillers have weak interfacial bonding with the polymer matrix, and interfacial debonding tends to occur during use, resulting in unstable performance. On the other hand, the use of chain extenders in polyamide synthesis or processing is an effective means of increasing its molecular weight, improving processability and mechanical properties of the final article. Isophorone diisocyanate (IPDI) is a cycloaliphatic diisocyanate, which contains two isocyanate (-NCO) groups of different reactivity in the molecule, a property that makes it uniquely advantageous in the modification of controlled polymers. In the prior art, the research of combining the functions of conductive fillers and chain extenders has focused on the use of a single type of diisocyanate (such as MDI) or simple pretreatment of the fillers, but it is often difficult to simultaneously optimize the filler dispersion, interface bonding, chain extender efficiency and the overall properties of the final composite. In particular, how to precisely control the directional bridging of chain extender molecules between two different dimensional nanomaterials (e.g., one-dimensional CNTs and two-dimensional graphene) to build a stable, efficient, synergistic conductive network remains a technical challenge. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide an antistatic PA10T composite material with excellent comprehensive performance. Another object of the present invention is to provide a composite chain extender with innovative structure for preparing the material and a controllable synthesis method thereof. The composite chain extender can simultaneously solve the problems of dispersion and interface of nano fillers, and realize efficient chain extension enhancement and antistatic function integration in a PA10T matrix. In order to achieve the above purpose, the invention adopts the following technical scheme: A high-strength high-temperature-resistant antistatic PA10T composite material and a preparation method thereof comprise the following steps: (1) 1, 10-diaminodecane, terephthalic acid, sodium hypophosphite serving as a catalyst and antioxidant 1010 are dispersed in deionized water by ultrasonic waves; (2) Transferring the dispersion liquid obtained in the step (1) into a high-temperature high-pressure reaction kettle, and stirring and reacting for 2 hours at 80 ℃ and 0.1MPa under the nitrogen atmosphere to obtain PA10T salt; (3) Heating for the second time under the condition of keeping stirring, heating to 240 ℃, and maintaining the pressure to 2.0-3.0 MPa for 4 hours; (4) Adding a composite chain extender IPDI-CNT-G into the reaction kettle, and continuously reacting for 2 hours at 240 ℃ and 2.5 MPa; (5) And (3) decompressing and cooling the reaction kettle, placing the prepolymer in a glass culture dish, placing the glass culture dish in a high-temperature vacuum drying oven, carrying out solid-phase tackifying for 4 hours, and then naturally cooling to normal temperature to obtain the high-strength